GPC - Glider Pilot Certificate Aircraft Systems and Instruments Questions and Answers

Question 1

A glider's pitot-static system provides data for which combination of instruments?

Accepted Answer

Airspeed indicator, altimeter, and vertical speed indicator (variometer)

Answer

The pitot-static system measures and compares ram air pressure (from the pitot tube) and static pressure (from the static port). This information is used by the airspeed indicator, the altimeter (which uses only static pressure), and the vertical speed indicator or variometer (which measures the rate of change of static pressure).

Question 2

During a pre-flight inspection, you notice the yaw string is frayed and partially detached. What is the primary consequence of flying with a malfunctioning yaw string?

Accepted Answer

Difficulty in maintaining coordinated flight.

Answer

The yaw string is a simple and crucial instrument that indicates whether the glider is in coordinated flight. It shows the direction of the relative wind. A malfunctioning yaw string makes it difficult for the pilot to sense and correct for adverse yaw, leading to inefficient and uncoordinated turns.

Question 3

What is the primary function of a total energy compensated variometer?

Accepted Answer

To indicate the rate of climb or descent due only to the movement of the surrounding air mass.

Answer

A total energy (TE) compensated variometer filters out changes in vertical speed caused by the pilot's control inputs (i.e., converting kinetic energy to potential energy, or 'stick thermals'). It aims to only show the vertical movement of the air the glider is flying through, which is crucial for locating and utilizing thermals for soaring.

Question 4

A pilot in a glider without flaps or a retractable undercarriage needs to significantly increase the rate of descent without a corresponding increase in airspeed. Which control system should be used?

Accepted Answer

Spoilers/Air Brakes

Answer

Spoilers, also known as air brakes, are deployed from the wings to disrupt airflow, which simultaneously decreases lift and increases drag. This allows the pilot to increase the glider's descent angle for landing or to escape strong lift without building up excessive airspeed.

Question 5

While performing a coordinated right turn in a glider, how are the primary flight controls manipulated?

Accepted Answer

Stick moves right, right rudder pedal is pressed.

Answer

To initiate a coordinated right turn, the pilot moves the control stick to the right to actuate the ailerons, causing the glider to roll. Simultaneously, the pilot applies right rudder pressure to counteract adverse yaw and keep the nose of the glider aligned with the flight path. Elevator back pressure is then typically required to maintain altitude in the turn.

GPC - Glider Pilot Certificate Practice Test

GPC - Glider Pilot Certificate Practice Test

GPC - Glider Pilot Certificate Aircraft Systems and Instruments Questions and Answers